Drummer and Ashford find themselves trapped with few options for survival; Anna tends to the wounded masses as Melba continues to hunt down her prey; the Rocinante crew struggles to survive as Naomi reunites with her true family.
Fallen World picks up where Dandelion Sky left off. That is with Holden having passed out on the floor of the Ring Station. Bobbie, seeing that Holden's vitals are fluctuating wildly, suggests the marines evacuate Holden to their dropship. When they get Holden to the skiff, Bobbie defibrillates Holden after his vitals crash. Holden's vitals recover but, he remains unconscious, with a highly active brain. Bobbie pulls for Holden to recover while the remaining marines blame Holden for the death of their commanding officer. Bobbie insists the orders are to return Holden to the Xuesen, which has sustained considerable casualties when the Ring System's maximum speed decreased significantly after Lt. Paolo Mayer threw a grenade inside the Ring Station.
On the Behemoth, Ashford and Drummer are stuck amongst the Mormon farming equipment, which has wedged both of them into spots they cannot move from. After nearly capturing a hand terminal with a mech arm, Ashford and Drummer discuss past experiences in their life histories and sing a belter shanty. Eventually, seeing she has no option, Drummer disengages a lock protecting her from being crushed. This frees Ashford from the position he is in and he is able to call help. When help arrives, they say Drummer will need gravity to survive the wounds she sustained while being crushed. Ashford looking at the drum that he is in announces he will be spinning up the drum of the Behemoth. Later, on the command deck, Ashford gives the order to spin up the drum of the Behemoth despite hesitation expressed by crew since it has never been spun up. When it is shown that the drum is maintaining ⅓g in its spin, Ashford, professing to be captain, announces to the flotilla that the Behemoth has gravity and is accepting anybody who needs medical attention.
On the Thomas Prince, Anna exits her quarters and accesses an emergency aid pack on the wall, where she extracts the emergency meds and injects herself. Suddenly aware of the situation, she sees all the floating bodies and blood in the corridor. Luckily, Anna was taking a nap in her room buckled in. Anyone not buckled in likely died or was hurt in the deceleration event. Anna follows others and heads toward the crowded mess hall where she learns that, due to the zero gravity, internal bleeding can be a death sentence since the blood will not properly drain, compared to a environment with gravity. She later finds Melba with a broken arm and leads her to the medical bay. She explains to Melba that all ships are being drawn to the station at the nucleus of the Slow Zone. Then, Anna receives a call from Tilly and tracks her severely injured new friend. Melba uses this opportunity to vanish. Tilly reveals she was attacked by Clarissa when she tried to help her, that she is the woman Anna knows as Melba, and she is going after James Holden. With tears welling up in hers eyes, floating in the corridor, Tilly passes with Anna alongside her holding hands. Anna goes back to the med bay to track down Melba Koh. Realizing she fled, Anna obtains tracking information from the doctor and a baton from a patient. Anna catches up to Clarissa as she is escaping out of an airlock with a mech suit on. Anna can only watch Clarissa exit the Thomas Prince and implores her to turn herself in and beg for mercy.
Across scenes spanning throughout the episode, Naomi recovers from the deceleration event, puts out a cabin fire, and she then leaves the skiff, continuing on her way to the Rocinante. When Naomi arrives to the quiet Rocinante, Naomi frantically searches for her crew and family. She first finds Alex, nearly unconscious floating in the galley. When Naomi asks Alex about Holden, he says something seemingly nonsensical that Holden is following Miller. Naomi then extracts Alex to the medical bay. She later finds an similarly nearly unconscious Amos, who says her hair changed before she also takes him to the medical bay. When an alarm begins to sound signalling a breach inside Rocinante's cargo bay, Naomi proceeds to check out the problem. Naomi is ambushed by Clarissa in a mech suit. Naomi attempts to fight back and maintain distance from Clarissa. When Naomi attempts to make an exit, Clarissa catches her by the waistband and throws her to the deck of the cargo bay. When Clarissa has Naomi by the throat, she demands to know where Holden is. Before Clarissa kills Naomi, Anna appears from behind and tases Clarissa's mech suit using the baton, disabling the suit.
In the last scene Bobbie finds Holden regaining consciousness. He claims to know how it all ends.
- Steven Strait as James Holden
- Cas Anvar as Alex Kamal
- Dominique Tipper as Naomi Nagata
- Wes Chatham as Amos Burton
- Frankie Adams as Bobbie Draper
- Shohreh Aghdashloo as Chrisjen Avasarala (credit only)
- David Strathairn as Klaes Ashford
- Nadine Nicole as Clarissa Melpomene Mao
- Cara Gee as Camina Drummer
- Genelle Williams as Tilly Fagan
- Elizabeth Mitchell as Anna Volovodov
- Andrew Rotilio as Diogo
- Brock Johnson as Grigori
- Dwight Ireland as T.P. Mess Hall Medic
- Hamed Dar as Pvt. Jed Trepp
- Nabil Ayoub as Behemoth Tech
- Rebecca Applebaum as T.P. Med Bay Doctor
- Sabryn Rock as Pvt. Riko Oshi
- A prior title for the episode was leaked as "Objects in Motion" but, as late as May 31st, it was replaced with "Fallen World".
- This episode's prior title refers to the abnormally low speed limit of the Slow Zone. More specifically, it refers to changes in speed especially abrupt ones applied to objects, bodies, and space vessels. More abstractly, it refers to Newton's First Law of Motion also colloquially known as "inertia".